Sunday, January 11, 2015

Wondering Willis Eschenbach makes more mischief with volcanoes

Wondering Willis Eschenbach has a well-earned reputation for wandering off on a tangent and avoiding scientific research. He's done the same today at WUWT (archived here, latest here). He decided that two recent papers relating to volcanic forcing are "wrong". Not because he took any notice of the content of the papers - he didn't. Not because he took any notice of the observations reported. He didn't. He decided to reject the months of hard work by multiple scientists, on the basis of his own five minutes of "research".

Climate models and volcanic forcing

The two papers found evidence of volcanic forcing, coming from two different perspectives:

One of the main points the scientists emphasised was that the CMIP5 models mostly assumed there was zero change in stratospheric volcanic forcing after 2000. They show that this assumption is not valid. Since 2005 in particular, there has been significant volcanic forcing, based on observations.

Significant increase in SAOD since 2005 (Ridley14)

This short section from the introduction of Ridley14 puts the findings and the implications for researchers in context:

It has often been assumed that only very explosive volcanic eruptions have pronounced effects on Stratospheric Aerosol Optical Depth (SAOD), and that since Mount Pinatubo in 1991, no eruptions have contributed noticeably to stratospheric aerosol content. However, observations since about 2005 revealed significant increases in SAOD [Stratospheric Aerosol Optical Depth] linked to a series of smaller eruptions [Vernier et al., 2011; Bourassa et al., 2012], with potentially important cooling effects on global climate [Solomon et al., 2011; Fyfe et al., 2013; Haywood et al., 2014].

Ridley14 found that, contrary to commonly held assumptions, it's been observed that there have been significant increases in SAOD since 2005. (The Stratospheric Aerosol Optical Depth (SAOD) indicates how transparent the stratosphere is. Aerosols can reflect sunlight, so they will limit the amount of solar energy getting to the surface.)

Santer14 complements the Ridley paper in that it found multiple signals of volcanic forcing. What they did was remove the ENSO signal so they could look at various parts of the system. Signals of volcanic forcing were detectable in near-global averages of rainfall. The signals were "statistically discernible" in:

The second Livermore-led study shows that the signals of these late 20th and early 21st eruptions can be positively identified in atmospheric temperature, moisture and the reflected solar radiation at the top of the atmosphere. A vital step in detecting these volcanic signals is the removal of the “climate noise” caused by El Niños and La Niñas.

“The fact that these volcanic signatures are apparent in multiple independently measured climate variables really supports the idea that they are influencing climate in spite of their moderate size,” said Mark Zelinka, another Livermore author. “If we wish to accurately simulate recent climate change in models, we cannot neglect the ability of these smaller eruptions to reflect sunlight away from Earth.”

WUWT has had at least three protests about the observed recent volcanic forcing now. Two that were just a copy and paste of press releases under a "claim" headline. Plus now a protest from Willis Eschenbach, disputing the findings - except that he didn't. Instead he disputed something that the papers didn't claim.

So what was Willis disputing and what did the papers report?

Willis was disputing any increase in volcanoes. That's not what the papers reported. What the scientists reported was a measurable radiative forcing from volcanoes, and a "significant" increase in SAOD since 2005. These are not the same thing.

Perturbed solar radiation and global surface temperature

Now, it is certainly possible that “small-magnitude volcanic eruptions substantially perturb incoming solar radiation”. There are lots of things that perturb incoming solar radiation, with clouds heading the list. Whether small volcano emissions in turn perturb the global surface temperature is a separate question.

The perturbation that Willis is talking about is the reflection of incoming solar radiation back to space by volcanic aerosols in the atmosphere. Willis is arguing that if there is less solar radiation reaching the surface, then it doesn't follow that there'll be a negative effect on global surface temperatures. In essence Willis is proposing there is no link between incoming solar radiation and global surface temperature, which seems odd, particularly for a climate science denier. (One common meme of deniers is that "it's the sun" (not greenhouse gases).

The authors didn't count volcanoes

But for eruptions to be an explanation for the current plateau in global warming, the authors would have to show a significant increase in volcanic eruptions in the 21st century. And unfortunately (but predictably) I see no sign in either paper that they have even tried to do that.

He's wrong. The authors don't need to show an increase in volcanic eruptions. They only need to show an increase in forcing, which is what they showed. They showed an observed increase in stratospheric aerosol optical depth as well as volcanic forcing signals in multiple independently-measured climate variables.

There doesn't have to have been a significant increase in volcanic eruptions in the 21st century for whatever volcanoes were erupting to have had an impact on global surface temperature. The impact depends on two main things - the composition and volume of volcanic aerosol ejected in a volcanic eruption, and where those aerosols are distributed in the atmosphere. The latter point depends a lot on where the volcano is located (material from equatorial volcanoes generally get dispersed more broadly around earth than do high latitude volcanoes).

As for what the scientists "even tried to do", well one of the papers, Ridley14, did list some of the potentially important eruptions. These included eruptions at the equator and at mid-to-high latitude - Ulawun, Shiveluch, Ruang, Reventador, Manam, Soufrière Hills, Tavurvur, Kasatochi, Sarychev, Eyjafjallajökull, and Nabro.

The Santer paper also looked at specific volcanic eruptions, contrary to what Willis claimed. For example, here are two extracts - of several (added a bit later by Sou):

Consider next the impact of the Tavurvur and Nabro eruptions. We obtain large negative values of ri{S,X} during 60-month periods which sample the effects of these volcanic events (Figs. 2A, B). In tropical averages of the Vernier et al. SAOD data, the peak values for Tavurvur and Nabro are in November 2006 and September 2011, respectively. In the near-global SAOD averages, the corresponding peak values are slightly time-shifted, and occur in December 2006 and August 2011....

...During the period influenced by the eruptions of Soufrière Hills, Tavurvur, and Nabro, the peak values of VRAW exceed 30% for near-global averages of SST (Fig. 4B). Clearly, the amplitude of these recent volcanic cooling signals is not negligible. The largest post-Pinatubo cooling signals are preferentially distributed in the final third of the "warming hiatus" period, and must therefore contribute to the hiatus.

Willis, in true fake sceptic fashion, decided to ignore the evidence provided. It would have demolished his story. Instead he went to the Smithsonian Institution's Global Volcanism Program to get data on volcanic eruptions. Which is fine. It was what he did with the data that was irrelevant, as far as these two research papers go. He didn't look at where the volcanoes erupted. He wouldn't have been able to tell how much impact any had on SAOD just by looking at the database. What he did was:

count the total numbers of eruptions by year

compute the average strength of all the volcanic eruptions combined

count the small pre- and post-2000 eruptions (VEI<3)

By the way, in regard to the last dot point, the particular volcanoes listed in Ridley14 as potentially important, are mostly VEI4 not VEI <3. I checked.

Anyway, Willis noticed little change in any of these and declared:

Well, the papers may be correct in their claim that the effect of eruptions on the clarity of the atmosphere may have been underestimated.

But they are absolutely not correct in the claim that this underestimation reveals the cause of the recent 18+ year plateau in temperatures as being eruptions. There is almost no post-2000 change in either the number of eruptions, the strength of eruptions, or the number of small eruptions.

All Willis did was confirm what Ridley14 stated was the basis of the commonly held assumption: the incorrect assumption that there has been zero change in stratospheric volcanic forcing in recent years. What he didn't do was look at the data for SAOD itself. I'd say he didn't bother reading the paper (or the press release) properly, he was so intent on trying to make out that scientists don't know nuffin' and that he, a wondering Willis from WUWT, knew more than all the world's experts.

Willis' strawman

Now Willis reckons the papers claim something that neither paper claims. Nor is it mentioned in the press release. Willis wrote (my bold) "...the claim that this underestimation reveals the cause of the recent 18+ year plateau in temperatures as being eruptions." But they didn't make that claim. The Ridley paper made no claim that the entire cause of the "recent plateau" was volcanoes. Nor did it talk about any so-called 18+ year pause. What it did mention was that globally averaged surface temperatures have "increased more slowly" over the past 15 years (not 18+ years) than during the previous two decades. The main focus of the papers was on the CMIP climate models not providing for recent increases in volcanic forcing. Ridley14 listed suggested mechanisms that could have contributed to the observed slowdown in globally averaged surface temperature, including but not limited to:

increased heat uptake by the oceans,

reduced solar output, and

recent volcanic eruptions.

The Santer paper also refers to the above, and adds [added a bit later by Sou]:

Uncertainties remain, however, and other modeling work suggests that key seasonal features of the "hiatus" are primarily attributable to changes in the Pacific Decadal Oscillation [Trenberth et al.]. Reliable quantitative partitioning of different external and internal contributions to the "hiatus" is still urgently required.

Willis completely ignores the data

Willis ignored the data and observations reported in the papers. He didn't attempt to explain the observed increase in SAOD as indicated in Figure 1 from Ridley14 (below). Nor did he make specific mention of the volcanoes shown in the top chart (a), which are listed in the caption. Click to enlarge:

Ridley14 was based on observational data. That's right. It's not pie in the sky stuff (instead it's aerosols in the sky stuff). The paper states the sources:

Based on observations from lidar retrievals, balloon-borne aerosol sondes, ground-based AERONET sun photometers, and satellite data, we estimate increases in global total SAOD since 2000, together with associated uncertainties.

Willis based his surmises on a primitive count of volcanoes, without regard for where those volcanoes were located, and without explaining the increase in SAOD since 2005 as reported in Ridley14. And without explaining the signals detected in multiple independently measured climate variables, as reported in the Santer paper.

Deniers have no uncertainty!

Not surprisingly, Wondering Willis was much more emphatic in his claim that the scientists are wrong, and much more certain in his statements than the scientists are. Ridley14 states at one point:

Figure 3 suggests a larger volcanic contribution to recent global temperature changes than has been inferred from previous work. Clearly, it is desirable to obtain a more reliable quantification of the contribution of this and other forcings (such as changes in solar activity) to the hiatus [Schmidt et al., 2014], and to reduce uncertainties in observational estimates of the decadal rate of change of global mean temperature [Cowtan and Way, 2014].

Fig. 3 - (a) Estimated global mean radiative forcing is shown for datasets from Sato et al. (orange), Vernier et al. (blue) and AERONET mean (black) with 25th to 75th percentile range (grey). The dotted line indicates the baseline model used in many climate model studies to date, which includes no stratospheric aerosol changes after 2000.(b) The temperature anomaly, relative to the baseline model, including the AERONET mean (black), median (white), and 25th to 75th percentile range (grey), Vernier et al. (blue), and Sato et al. (orange) forcing computed for each dataset (c) the total global temperature change predicted by the Bern 2.5cc EMIC in response to combined anthropogenic and natural forcing, including the reduced warming when considering the stratospheric aerosol forcing from the three datasets.Source:Ridley14

The point is that most models had zero change in stratospheric aerosol forcing from volcanic activity. The Ridley team showed that there has been some significant forcing in recent years.

The climate model simulations evaluated in the IPCC fifth assessment report [Stocker et al., 2013] generally assumed zero stratospheric aerosol after about 2000, and hence neglect any cooling effect of recent volcanoes (see Figure 3 of Solomon et al., 2011). We find that satellite-based SAOD datasets generally agree well with SAOD inferred from lidar measurements above 15 km; however, they do not capture the full magnitude of the SAOD signal above the tropopause.

A bunch of deniers vs an interdisciplinary team of experts

The Livermore-led research involved a large interdisciplinary team of researchers with expertise in climate modeling, satellite data, stratospheric dynamics, volcanic effects on climate, model evaluation, statistics and computer science.

Now, Willis’s Rule of Author Count says that the quality of any study is inversely proportional to the square of the number of listed authors.

If Willis had a grasp of climate modeling, satellite data, stratospheric dynamics, volcanic effects on climate, model evaluation, statistics and computer science then his word might have meant something. Since the only accreditation the mob of WUWT deniers have is membership of the Scientific Illiterati Society, I propose to give their opinion the weight it deserves - which is zero. A stratospheric fail!

Based on my observations of WUWT, the more significant a scientific paper in denierland, the bigger the challenge to denialist memes, the more dumb protest articles there are on denier blogs. These papers aren't nearly as significant to deniers as Marcott13 or Recursive Fury or Cook13, for example.

From the WUWT comments

Curt asks a question:

January 9, 2015 at 7:12 pm
My understanding is that conventional wisdom says that “small” volcanic eruptions have less than proportional effect because their ejections don’t get that high in the atmosphere and are quickly rained out. Is this being challenged?

The two papers don't challenge that. What they showed was that some of the material from moderate volcanoes does get up in the stratosphere, and the part that wasn't being picked up was in the stratosphere below 15km.

motogeek rather rudely says he prefers pseudo-science to science though not in so many words:

January 9, 2015 at 7:21 pm
*sigh* Most of the warmista’s won’t even admit there is a pause *at all* when you try to discuss the pause with them. I do see that articles like this have their place (getting them to admit there is a pause at all). How much can people have their heads shoved up their asses?

latecommer2014 is an ignorant climate conspiracy theorist. The type of person that forms the core target market of Anthony Watts:

January 9, 2015 at 9:19 pm
Why do we even consider these frauds. They are political scientist working at the bid of their controllers and contemptible

bones is so relieved. He's found someone to tell him that all the scientific experts are wrong. More proof that Anthony Watts is attracting the people he wants.

January 9, 2015 at 7:39 pm
Willis, Excellent. Thanks for your effort. My gut feeling was that the studies were nonsense, but your finding and analyzing the relevant data took all of the guesswork right out of it. Thanks, much appreciated!

Jeff L didn't read either paper, so doesn't know (or care) that Willis is wide of the mark. It's sufficient for him that a crank like Willis Eschenbach claims he is right and all the experts are wrong:

January 9, 2015 at 9:11 pm
Beautiful data Willis – I love it when alarmist arguments can be quickly dismissed with a little basic research & data. Exposes them for the political agenda driven bunch they are versus the science driven bunch skeptics are.
Well done!

Steven Mosher tried to set Willis straight, though he, too, misses the point that the authors weren't claiming that the slowdown was all down to volcanic aerosols - Ridley estimated volcanoes shaved 0.05 to 0.12 °C off the global surface temperature:

January 9, 2015 at 9:16 pm“But for eruptions to be an explanation for the current plateau in global warming, the authors would have to show a significant increase in volcanic eruptions in the 21st century. ”
No. they would not have to show this.
Showing it would help, but its not necessary.
What’s important is total forcing.

I see that later on, Willis Eschenbach doubles down on his denial and refusal to consider the evidence, and responds to Steven Mosher with:

January 9, 2015 at 11:22 pm (extract)
...No. they would not have to show this.
Showing it would help, but its not necessary.
What’s important is total forcing.
Say what? Given that as I have shown, there is no difference in the volcanic eruptions during the time of increasing temperatures and the time of the plateau in warming, then how on earth can the eruptions be the reason for the pause?
You’ll have to explain that claim a whole lot better than you’ve done so far, Mosh.
w.

rishrac, I think, is trying for sarcasm. When it comes from a Dunning Kruger candidate it's not effective. They just look foolish.

January 9, 2015 at 9:53 pm
So does that mean the heat is still hiding in the oceans? Skeptics are not the intended audience for the “it’s the volcanoes” line. Why would they think someone wouldn’t look at the number and size? Oh.. I know, the truly faithful. It has to be co2!!! It’s a villain just lurking around the shadows, just waiting. That tipping point must be around here somewhere.

I don't know what is going on in the head of TimTheToolMan - he doesn't understand the terms he's using is my guess. He's not making sense:

January 9, 2015 at 10:05 pm
Willis writes “Well, the papers may be correct in their claim that the effect of eruptions on the clarity of the atmosphere may have been underestimated.”
Only with the assumption of a very high sensitivity…and there’s not a lot of evidence for that.
Its another case of “making stuff up” to suit their message.

There have been a lot more comments since I wrote this article. In particular there was a good comment from Frank who wrote that there has been an increase in VEI4 volcanoes:

January 10, 2015 at 12:33 am
Willis: The total number of eruptions is not important. Neither is the log mean annual VEI or the number of volcanoes with VEI <3. These are all straw men. The important factor is the number eruptions capable of transferring a significant amount of aerosol above the tropopause (where it will persist). The authors claim to have measured an increase in total aerosol since 2000 and claim it comes from volcanos weaker than the VEI 5 and 6 volcanoes that have traditionally been associated with cooling. That means you should have concentrated your analysis on volcanoes with VEI = 4. There were 14 volcanos with VEI = 4 between 2002 and 2011 and one with VEI = 5. Between 1900 and 1999, there were only 52 volcanoes with VEI = 4, 10 with VEI = 5 and three with VEI = 6. There clearly have been an unusually large number of VEI = 4 volcanoes during the hiatus than in earlier decades.

The key question is whether these previously ignored volcanoes resulted in higher levels of stratospheric aerosol than during earlier decades when VEI = 4 volcanoes were ignored. Most of the measurement techniques used during the hiatus were not available in earlier years. When the first paper was not behind a pay-wall, I thought that the methods that were used both before and during the hiatus gave contradictory results before the hiatus and therefore an ambiguous increase during the hiatus. The uncertainty in increase in aerosol forcing was about 50% of the total increase and this may have been a 25%-75% confidence interval.

There were also lots of people who believe the libel against scientists they've read on disinformation blogs, and were determined to spread it further. They fell for the Serengeti Strategy and, being fake sceptics, are satisfied with any lie as long as it supports what they want to believe.

7 comments:

I look at those reports and think, "That's interesting, now we have to take ordinary volcanic activity into account rather than just the biggies."

And I have to change the way I think about this stuff from now on. Because I've been working on the basis that if it's not big and spectacular like Pinatubo then it's not going to matter much. Turns out that the dribs and drabs of regular volcanic activity are like all the other contributors to climate. The more there is of something, no matter how unremarkable those things are, the more likely it is there'll be some impact somewhere in the system. The only issue is in deciding how much time and effort should go into measuring that impact. Turns out, for this particular exercise, the time and effort came up with a worthwhile result and all of us now have to be aware of it.

Other people don't have to change anything for any reason at any time it seems.

I read the top-level link to this post, then read WW's post on WUWT, so as not to be influenced by what I read here. I noticed first (because I checked out the links) that WW quoted the second paper's abstract in full, but didn't quote the first in full, missing out the authors' actual conclusion, that

"Incorporating these estimates into a simple climate model, we determine the global volcanic aerosol forcing since 2000 to be −0.19 ± 0.09 Wm−2. This translates into an estimated global cooling of 0.05 to 0.12°C. We conclude that recent volcanic events are responsible for more post-2000 cooling than is implied by satellite databases that neglect volcanic aerosol effects below 15 km."

... thus following the grand old maxim of "omit or ignore the bit or bits that are inconvenient". Another tactic is just as old, and just as prevalent, which is to "move the goalposts", as WW did in his interaction with Frank. You may, if you wish, conclude that I have little respect for Willis' Wonderings, and you'd be right.

Someone who's not right is "Anonymous" who concluded in a reply to my comment on another post that "I suspect that your skepticism is closer to denial of general climate science", on which point he was totally wrong.

I must revise my opinions. I had been led to believe by WUWT that the very best papers were those that included a number of people who were surprised (and perhaps dismayed) to discover they had been counted as an author.

Sou - you missed a WW fiction back in 2013. In The Most Important Sea Level Graph, WW has an anonymous National Tidal Centre (Australia) author apparently using a statistic (not available until Jan 2013 at the earliest) in a report written in 2011, which analysed data to end 2010. WW claimed that monthly sea-level data has to be adjusted "to remove tidal components". That's crap. I pulled him up on that, but was ignored.

In fact tidal frequencies are removed from hourly data using aDoodson filter to give daily values, which are then averaged to give monthly values. WW showed a chart for three Pacific Islands using data to 2012, then claims an NTC report for Majuro (Marshall Islands) adjusted the trend through 2010 twice -

"So for example, the measured change in the sea level at the Majuro B (SEAFRAME) tide gauge was +5.6 mm/year 1993-2010. But after subtracting the tidal effects, it drops to 4.3 mm/year. And after removing land subsidence effects, the actual trend was estimated by the SEAFRAME folks at 3.8 mm/year."

The "5.6" figure is Willis' own, from his chart. It's not to be found in the NTC report, and neither is the "removal of tidal components".

There's more crap in the comments. For example, WW tells a dissenting commenter that "Finally, you need to bear in mind that not one of the records you accessed has had the tidal effect filtered out. Those records are the SUM of the slow tidal changes and the underlying sea level changes (if any). The sun-moon tidal cycle roughly repeats with an 18.6-year period, with a closer return to original conditions every three cycles (55.8 years). That’s why you need fifty years of tide gauge data to determine the change in the underlying sea level."

Pure, unadulterated crap - as I recall, he edited his reply to include the 18.6 year nodal cycle after I'd brought it up. There's no "closer return to original conditions every three cycles (55.8 years)" - he made that up too. WW is a "bear of little brain" and no integrity.

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All you need to know about WUWT

WUWT insider Willis Eschenbach tells you all you need to know about Anthony Watts and his blog, WattsUpWithThat (WUWT). As part of his scathing commentary, Wondering Willis accuses Anthony Watts of being clueless about the blog articles he posts. To paraphrase:

Even if Anthony had a year to analyze and dissect each piece...(he couldn't tell if it would)... stand the harsh light of public exposure.

Definition of Denier (Oxford): A person who denies something, especially someone who refuses to admit the truth of a concept or proposition that is supported by the majority of scientific or historical evidence.
‘a prominent denier of global warming’
‘a climate change denier’

Alternative definition: A former French coin, equal to one twelfth of a Sou, which was withdrawn in the 19th century. Oxford. (The denier has since resurfaced with reduced value.)